Microfluidics is a relatively new area of technology that is developing as a result of advances in microfabrication, biology, and information processing research that is focusing attention on the realization of compact systems and even single chip level implementations that can run collections of biological processes on tiny samples of biological fluids and materials. For example, there is an extreme urgency for developing cheap and fast assays for toxin identification based on analysis of blood, saliva, tissues, and the protein or DNA extracted from these sources. Also, large and ready markets exist for point of care diagnostic tests that similarly draw health, disease susceptibility, and drug therapy indicator information from these and other sources. Part of the difficulty of realizing these systems is gathering the knowledge about how to process and extract information from such samples. Another part of the problem is realizing safe, effective, inexpensive, and durable systems for running the bio-process reactions and readouts necessary for researching and eventually commercializing the envisioned tests. Examples of the processes that might be used are fluid gathering, filtering, mixing with reagents, managing the flow of small quantities of fluids and biomaterials through systems of channels and elements involved in performing the reactions and reading out the results. There is pressure on developers of bioassay platforms to develop smaller, even credit card or implant-able chip size means for running such tests.